The diet of farm animals, such as cattle, is usually prescribed by a specialist, typically a nutritionist. In detail, the nutritionist identifies, by way of laboratory analysis, a series of information on chemical components and nutritional values, such as starch, proteins, dry matter etc., that characterize each of the foods prescribed in the animal's alimentary diet and then determines, based on the identified chemical components and nutritional values for each food and on the base of animals nutritional needs resulting from their physical and productive conditions, the correct ration of food, in terms of absolute weight for each food, to be introduced in the alimentary diet.
In many livestock farms, the dosage of each food and the preparation of the food ration to be administered to each animal are made via a mixer wagon, in which are loaded by way of mechanical shovels or other loading systems mounted on motor vehicles, the different foods based on respective weights of alimentary diet predetermined by the nutritionist.
The latest generation mixer wagons are equipped with a weighing system, which comprises one or more load cells coupled with the frame and/or container body of the mixer wagon to detect the weight of the foods loaded into the container body and an electronic control unit connected to the load cells to measure moment by moment, the weight of the food deposited by a mechanical shovel or any other charging system in the container body and check that the loaded food weight reaches the respective predetermined weight. In detail, the electronic control unit comprises a memory for memorizing at least one recipe for foods to be loaded into the mixer wagon, a processing and control module configured to control, based on the recipe, the weight of foods as they are loaded into the mixer wagon and a display to indicate to an operator the weight measured moment by moment and the achievement of the absolute weight of the food contained in the recipe. Alternatively, the electronic control unit is connected to an external electronic device, such as a handheld computer to receive from the latter the food recipe.
It often happens that the various foods that make up the recipe should be taken from different stocking areas or depots subject to prolonged exposure to the weather conditions, which modify, as known, the percentages of chemical components of food and, therefore, significantly alter the nutritional values of food. Therefore, with the same “fresh weight” of food fed to the animal, the nutritional values actually administered may vary significantly from those provided by the “theoretical” alimentary diet established by the nutritionist. Consequently, nutritionally imbalanced conditions can result in the animal, which can also adversely affect the physical condition of the animal and however lead indirectly to a decline in quality and quantity of the products obtained from the animal itself (milk, manure, etc.). Nutritionists are well aware of this risk and therefore tend to provide diets to meet the nutritional needs of animals even in worst case conditions, by administering, in most cases, diets with excess proteins that drives up food costs more than actually necessary. It should be added that when an animal ingests a quantity of proteins in excess of its needs, the animal transforms, through the digestive cycle, the excess proteins in nitrogenous compounds that are expelled in the form of stool: the environmental impact is not negligible and of course proportional to the number of animals given an alimentary diet with excess proteins.